SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ae9eed0977b3e1a33b3ff62c0a94c9d42049c247cc02d930b42d9c66935a7d6' 
  AND token = 'i8eRbZKtP7ZjuTto1rbGkr5NLCzKluxZvuTvX9xfedg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}